Description

Key Characters:

Growth Form: Erect perennial herbs or shrubs, sometimes somewhat scandent or prostrate, usually scabrous or hispid, sometimes tomentose.

Stems: Stems quadrangular, often with stout prickles.

Roots:

Leaves: Leaves simple. Opposite and decussate (pairs of leaves alternating 90 degrees between nodes) or ternate. Blades often rugose, fragrant when bruised. Margins usually dentate or serrate. Petiolate. Stipules absent.

Flowers: Flowers in dense, usually axillary, cylindrical, indeterminate spikes or heads. Flowers bisexual (perfect). Each flower subtended by an oblong to lanceolate or ovate bract. Calyx small, membranous, truncate or sinuate–dentate. Corolla slightly irregular, red, yellow, purple, blue, or white, salverform, imbricate. Stamens 4, in 2 pairs, inserted near middle of and included in corolla tube; anthers dithecal, opening by longitudinal slits. Ovary superior, 1-carpellate, 2-celled, placentation axile; ovules 1 per cell, erect, anatropous; style usually short; stigma thick, oblique or nearly lateral.

Fruit: Fruit drupaceous; 2–celled or splitting into 2 pyrenes; exocarp usually fleshy at maturity; rarely dry; endocarp hard. Seeds 1 per cell.

Ploidy:

Habitat:

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